Applying Term Weight Techniques to Event Log Analysis for Intrusion Detection

Strong similarities exist between intrusion detection and information retrieval. This paper explores the application of probabilistic information retrieval techniques to log analysis for host-based intrusion detection. Using information retrieval techniques may yield significant improvements to the performance of intrusion detection systems. This paper provides a brief review of current relevant research in intrusion detection and log analysis, introduces information retrieval methods appropriate for intrusion detection, and evaluates the effectiveness an experimental log analysis system using the 1999 DARPA Intrusion Detection Evaluation data sets. The system is based on Bayesian probability theory and uses a TF-IDF term weight measure to identify anomalies

Planar near-field scanning for compact range bistatic radar cross-section measurement

The design, construction, and testing of a low cost, planar scanning system to be used in a compact range environment for bistatic radar cross-section (bistatic RCS) measurement data are discussed. This scanning system is similar to structures used for measuring near-field antenna patterns. A synthetic aperture technique is used for plane wave reception. System testing entailed comparison of measured and theoretical bistatic RCS of a sphere and a right circular cylinder. Bistatic scattering analysis of the ogival target support, target and pedestal interactions, and compact range room was necessary to determine measurement validity

Pockets of Proterozoic hydrocarbons and implications for the Archaean

Precambrian biomarkers convey invaluable information about the early evolution of life, ancient ecosystems, redox conditions, climate and depositional environment and prospective petroleum systems. They are however thermally unstable, easily obliterated by contamination and thus extremely difficult to find. This is particularly true if conditions favourable for biomarker preservation had to prevail for more than 2.5 billion years – the prerequisite for finding Archaean biomarkers. Many organic geochemists abandoned this hope after original discoveries of Archaean biomarkers proved to be of younger origin [1,2] but our study of ca. 550-825 Ma old sediments from the Centralian Superbasin now shows that biomarkers can be preserved in distinctive pockets in seemingly barren areas, even if sections are metamorphosed in parts. Most Centralian sections seem empty. Yet, eventually we identified intervals with preserved biomarkers in three drill cores. A detailed investigation of 825 Ma sediments in drill core Mt Charlotte-1 revealed maturity variations that are most likely due to hydrothermal influence and in turn control the hydrocarbon preservation. Sediments might appear metamorphosed after localized, subtle alteration by hydrothermal fluids but protected intervals can still contain biomarkers. The same might be true for Archaean sediments and we might still find those protected intervals with indigenous biomarkers that allow us to glimpse the early life on earth

Diagenetic evolution of lower Jurassic platform carbonates flanking the Tazoult salt wall (Central High Atlas, Morocco)

Platform carbonates diagenesis in salt basins could be complex due to potential alterations of fluids related and non‐related to diapirism. This paper presents the diagenetic history of the Hettangian to Pliensbachian platform carbonates from the Tazoult salt wall area (central High Atlas, Morocco). Low structural relief and outcrop conditions allowed to define the entire diagenetic evolution occurred in the High Atlas diapiric basins since early stages of the diapiric activity up to their tectonic inversion. Precipitation of dolomite and calcite from both warmed marine‐derived and meteoric fluids characterised diagenetic stages during Pliensbachian, when the carbonate platforms were exposed and karstified. Burial diagenesis occurred from Toarcian to Middle Jurassic, due to changes of salt‐induced dynamic related to increase in siliciclastic input, fast diapir rise and rapid burial of Pliensbachian platforms. During this stage, the diapir acted as a physical barrier for fluid circulation between the core and the flanking sediments. In the carbonates and breccias flanking the structures, dolomite and calcite precipitated from basinal brines, whereas carbonate slivers located in the core of the structure, were affected by the circulation of Mn‐rich fluids. The final diagenetic event is characterised by the income of meteoric fluids into the system during uplift caused by Alpine orogeny. These results highlight the relevant influence of diapirism on the diagenetic modifications in salt‐related basins in terms of diagenetic events and involved fluids

A sea surface temperature reconstruction for the southern Indian Ocean trade wind belt from corals in Rodrigues Island (19° S, 63° E)

The western Indian Ocean has been warming rapidly over recent decades, causing a greater number of extreme climatic events. It is therefore of paramount importance to improve our understanding of links between Indian Ocean sea surface temperature (SST) variability, climate change and sustainability of tropical coral reef ecosystems. Here we present monthly resolved coral Sr ∕ Ca records from two different locations from Rodrigues Island (63° E, 19° S) in the south-central Indian Ocean trade wind belt. We reconstruct SST based on a linear relationship with the Sr ∕ Ca proxy with records starting from 1781 and 1945, respectively. We assess relationships between the observed long-term SST and climate fluctuations related to the El Niño–Southern Oscillation (ENSO), the Subtropical Indian Ocean Dipole Mode (SIOD) and the Pacific Decadal Oscillation (PDO) between 1945 and 2006, respectively. The reproducibility of the Sr ∕ Ca records is assessed as are the potential impacts of diagenesis and corallite orientation on Sr ∕ Ca–SST reconstructions. We calibrate individual robust Sr ∕ Ca records with in situ SST and various gridded SST products. The results show that the SST record from Cabri provides the first Indian Ocean coral proxy time series that records the SST signature of the PDO in the south-central Indian Ocean since 1945. We suggest that additional records from Rodrigues Island can provide excellent records of SST variations in the southern Indian Ocean trade wind belt to unravel teleconnections with the SIOD/ENSO/PDO on longer timescales

Cell surface antigens in renal tumour cells: detection by immunoluminescence and enzymatic analysis

Two renal cell carcinoma cell lines (49RC 43STR and 75RC 2STR) were characterized by detection of the cell surface proteins: CD44(var), intercellular adhesion molecule-1 (ICAM-1), urokinase-type plasminogen activator (uPA) and its receptor and aminopeptidase N (APN). To detect their localization the immunoluminescent technique was used. In addition, the enzyme activity of uPA and APN was investigated in cell suspensions as well as in monolayers. The latter procedure was more advantageous since the additional use of HPLC permits a single registration of the fluorescent hydrolysis-product AMC (7-amino-4-methylcoumarin) without interference by cellular autofluorescence or non-reacted fluorescent substrate. Unlike 75RC 2STR, the cell line 49RC 43STR expressed high levels of uPA and APN. Contrary to that the cell line 75RC 2STR expressed high levels of ICAM-1 and CD44(v6), whereas 49RC 43STR showed a low level of ICAM-1 and no distinct light signal with anti-CD44(v6). The uPA activity was measured directly as well as indirectly (via plasmin) with the substrate Z-Gly-Gly-Arg-AMC. Both activator and plasmin activity were inhibited by D-Val-Phe-Lys-CMK and phenylmethylsulfonyl fluoride. The anti-catalytic antibody to uPA and that to uPA receptor were found to be inhibiting the uPA activity in a concentration-dependent manner. APN activity was assayed using alanine-p-nitroanilide. Peptidase activity was effectively inhibited by 1,10-phenanthroline and partly inhibited by ethylenediamine-tetraacetic acid. © 2001 Cancer Research Campaignhttp://www.bjcancer.co

Assessing the carcinogenic potential of low-dose exposures to chemical mixtures in the environment: focus on the cancer hallmark of tumor angiogenesis

One of the important ‘hallmarks’ of cancer is angiogenesis, which is the process of formation of new blood vessels that are necessary for tumor expansion, invasion and metastasis. Under normal physiological conditions, angiogenesis is well balanced and controlled by endogenous proangiogenic factors and antiangiogenic factors. However, factors produced by cancer cells, cancer stem cells and other cell types in the tumor stroma can disrupt the balance so that the tumor microenvironment favors tumor angiogenesis. These factors include vascular endothelial growth factor, endothelial tissue factor and other membrane bound receptors that mediate multiple intracellular signaling pathways that contribute to tumor angiogenesis. Though environmental exposures to certain chemicals have been found to initiate and promote tumor development, the role of these exposures (particularly to low doses of multiple substances), is largely unknown in relation to tumor angiogenesis. This review summarizes the evidence of the role of environmental chemical bioactivity and exposure in tumor angiogenesis and carcinogenesis. We identify a number of ubiquitous (prototypical) chemicals with disruptive potential that may warrant further investigation given their selectivity for high-throughput screening assay targets associated with proangiogenic pathways. We also consider the cross-hallmark relationships of a number of important angiogenic pathway targets with other cancer hallmarks and we make recommendations for future research. Understanding of the role of low-dose exposure of chemicals with disruptive potential could help us refine our approach to cancer risk assessment, and may ultimately aid in preventing cancer by reducing or eliminating exposures to synergistic mixtures of chemicals with carcinogenic potential

Defense spending databases for countries in the Asia-Pacific Region: an analysis and comparison

The purpose of this research was to identify and analyze a select number of unclassified databases that cover defense spending and other defense related criteria for countries in the Asia-Pacific region. A thorough search was first conducted for databases with defense information on countries in the Asia- Pacific region. Initial sorting criteria were identified and applied to create a list of databases to be evaluated in detail. These databases were then evaluated and discussed in detail using additional evaluation criteria that were developed. Conclusions were then drawn, and recommendations made, for the best databases to be used by defense and policy analysts in the future. This research recommended the following databases. For defense spending information, the Australian Defense Intelligence Organization's Defense Economic Trends in the Asia-Pacific 1999 was recommended. For defense capabilities information, the International Strategic Studies Association's Defense and Foreign Affairs Handbook was recommended. For arms sales and transfers information, the SIPRI yearbook was recommended for use. The best all around defense database on the Asia-Pacific region was judged to be the International Institute of Strategic Studies' Military Balance 2000/2001.http://archive.org/details/defensespendingd109451085

Computer Security Information Retrieval APPLYING TERM WEIGHT TECHNIQUES TO EVENT LOG ANALYSIS FOR INTRUSION DETECTION

Strong similarities exist between intrusion detection and information retrieval. This paper explores the application of probabilistic information retrieval techniques to log analysis for host-based intrusion detection. Using information retrieval techniques may yield significant improvements to the performance of intrusion detection systems. This paper provides a brief review of current relevant research in intrusion detection and log analysis, introduces information retrieval methods appropriate for intrusion detection, and evaluates the effectiveness an experimental log analysis system using the 1999 DARPA Intrusion Detection Evaluation data sets. The system is based on Bayesian probability theory and uses a TF-IDF term weight measure to identify anomalies